.bac_img{
    position: relative;
    width: 100vw;
    height: 100vh;
    background-size: cover;
    background-image: url(../image/login-bg.png);
}
.login_box{
    box-sizing: border-box;
    padding: 50px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(20%,-50%);
    border-radius: 10px;
    width: 500px;
    height: 350px;
    background-color: white;
}
.title{
    width: 100%;
    height: 50px;
    text-align: center;
    line-height: 50px;
    font-size: 25px;
    font-weight: 530;
}
.main{
    display: flex;
    flex-direction: column;
    justify-content: space-evenly;
    width: 100%;
    height: 70%;
}
.readme{
    display: flex;
    align-items: center;
    width: 100%;
    height: 30px;
    font-size: 14px;
}
a{
    text-decoration: none;
    color: #83c0ff;
}
.footer{
    opacity: .6;
}